Field of the Invention
The present invention relates to a poly(ethylene-aliphatic diene) copolymer having improved properties such as adhesion, printability and the like by introducing a variety of functional groups, and a preparation method thereof.
Description of the Related Art
Thermoplastic elastomers (TPEs) consist of soft segments having elasticity and hard segments preventing deformation due to thermoplasticity. TPEs may be formed by a method identical to a method of processing thermoplastics. TPEs also have elasticity, which is a property of thermoplastic rubber, at room temperature. By varying amounts of soft segments and hard segments in TPEs, TPEs having various properties may be produced.
TPEs are utilized as a material in various fields such as shoes, adhesives, vehicles, industrial supplies, constructions, civil engineering, marine industries, wires, cables, electronic devices, electrical appliances, sports equipment, packing materials, medical supplies and the like. TPEs are also used in large quantities as a plastic conditioner or as compatibilizers for polymer alloys. The alloys using TPEs are utilized in electrical and electronic devices, cameras and the like. In addition, TPEs may provide properties such as conductivity, photosensitivity, selective separation and the like and, as such, may be utilized in fields requiring high functionality such as electrical engineering, optics, medicine, and printing. TPEs are attracting considerable attention due to such high functionality thereof. Particularly, in medical supplies, TPEs may be utilized as a high purity rubber material, without a vulcanization agent. People have great interest and are studying for such an advantage of TPEs.
Research and development for types of soft segments and hard segments, molecular weights, and arrangements of TPE products are being conducted. Thus, TPE products having high performance and functionality are being produced and TPE product types are being varied. In addition, demand for TPEs is increasing every year due to continuous use development and concern on the environment. As a result, TPE market is being expanded actively.
TPEs are classified into thermoplastic olefinic elastomers (TPO), thermoplastic styrenic block copolymers (SBC), thermoplastic polyurethanes (TPU), thermoplastic polyamides (TPAE), thermoplastic polyester elastomers (TPEE), and the like.
Most TPO based TPEs are block copolymers in which polypropylene, polystyrene, polyethylene, nylon, styrene-acrylonitrile and the like, which are hard, and ethylene propylene diene (EPDM) rubber, natural rubber, styrene-butadiene rubber (SBR) and the like, which are soft, are copolymerized. Among these, a random block copolymer consisting of ethylene/α-olefin is the most widely utilized. Most TPO based TPEs are a random copolymer. Recently, to improve properties of TPO based TPEs, methods using metallocene catalysts or introducing living polymerization has been proposed (Olefin-diene Copolymer, Korean Application Pub. Nos. 2012-0052385 and 2011-0114475).
As SBC based TPEs, Kraton Performance Polymers Inc. prepares and sells SBS (polystyrene/polybutylene binary copolymer), SEPS (polystyrene/poly(ethylene-propylene)/polystyrene terpolymer), SEBS (polystyrene/poly(ethylene-butylene))/polystyrene terpolymer) and the like under the registered trademark “Kraton”. As similar products to the SBC based TPEs, a variety of polymers such as Solprene and Calprene series of Dynasol, SEPTON of KURARAY CO., LTD., and the like are commercially available.
Molecules of TPO based or SBC based TPEs are non-polar. Thus, the TPO based or SBC based TPEs do not adhere easily to metal, wood and plastic materials, and do not have miscibility with other polymers. For these reasons, use of the TPO based or SBC based TPEs is limited.